Systems and Control
Behavioral Generative Agents for Power Dispatch and Auction
Shaoze Li, Justin S. Kim and Cong Chen
This paper presents positive initial evidence that generative
agents can relax the
rigidity of traditional mathematical models for human decision-making in power dispatch and auction settings. We design two proof-of-concept energy experiments with generative
agents powered by a large
language model (LLM). First, we construct a home battery management testbed with
stochastic electricity prices and blackout interventions, and
benchmark LLM decisions against dynamic programming. By incorporating an in-context learning (ICL) module, we show that behavioral patterns discovered by a stronger
reasoning model can be transferred to a smaller LLM via example-based prompting, leading
agents to prioritize post-blackout energy reserves over short-term profit. Second, we study LLM
agents in simultaneous ascending auctions (SAA) for power network access, comparing their behavior with an optimization
benchmark, the straightforward bidding strategy. By designing ICL
prompts with rule-based, myopic, and strategic objectives, we find that structured prompting combined with ICL enables LLM
agents to both reproduce economically rational strategies and exhibit systematic behavioral deviations. Overall, these results suggest that LLM-powered
agents provide a flexible and expressive testbed for modeling human decision-making in power system applications.
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Signal Processing
Multi-Mode Pinching-Antenna Systems: Mode Selection or Mode Combining?
Xiaoxia Xu, Xidong Mu, Yuanwei Liu et al. (+1 more)
This letter investigates multi-mode pinching
antenna systems (PASS), where signals of multiple orthogonal modes can be transmitted within a dielectric waveguide and radiated by pinching
antennas (PAs). This enables mode-domain multiplexing for efficient multi-user communications using a single waveguide. In particular, two operating protocols are proposed, namely mode selection and mode combining. Mode selection enforces each PA to predominantly radiate signal power of one single mode, while mode combining allows each PA to flexibly radiate power of multiple modes. Based on the two protocols, a sum rate maximization problem is formulated for multi-mode PASS-enabled multi-user downlink communications, where the transmit beamforming, PA positions, and PA propagation constants are jointly optimized. To address this rapidly oscillating and highly nonconvex problem, a particle swarm optimization (PSO) based Karush-Kuhn-Tucker (KKT)-parameterized beamforming (PSO- KPBF)
algorithm is proposed. KKT-conditioned solutions are exploited to guide the swarm search, thus reducing the search space and achieving fast convergence. Numerical results demonstrate that: 1) Even using a simple uniform mode-combining design, the multi-mode PASS significantly outperform conventional single-mode PASS and hybrid beamforming systems; and 2) Mode combining achieves high spectral efficiency, while mode selection approximates its performance with a lower hardware complexity. Code is released at https://github.com/xiaoxiaxusummer/multi_mode_pinching_
antenna
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All authors Xiaoxia Xu, Xidong Mu, Yuanwei Liu, Arumugam Nallanathan
Systems and Control
Integrating Lagrangian Neural Networks into the Dyna Framework for Reinforcement Learning
Shreya Das, Kundan Kumar, Muhammad Iqbal et al. (+4 more)
Model-based reinforcement learning (MBRL) is sample-efficient but depends on the accuracy of the learned dynamics, which are often modeled using black-box methods that do not adhere to physical laws. Those methods tend to produce inaccurate predictions when presented with data that differ from the original training set. In this work, we employ Lagrangian neural networks (LNNs), which enforce an underlying Lagrangian structure to train the model within a Dyna-based MBRL framework. Furthermore, we train the LNN using
stochastic gradient-based and state-estimation-based optimizers to learn the network's weights. The state-estimation-based method converges faster than the
stochastic gradient-based method during neural network training. Simulation results are provided to illustrate the effectiveness of the proposed LNN-based Dyna framework for MBRL.
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All authors Shreya Das, Kundan Kumar, Muhammad Iqbal, Outi Savolainen, Dominik Baumann, Laura Ruotsalainen, Simo Särkkä
Systems and Control · Cross-listed from cs.RO
Adaptive Entropy-Driven Sensor Selection in a Camera-LiDAR Particle Filter for Single-Vessel Tracking
Andrei Starodubov, Yaqub Aris Prabowo, Andreas Hadjipieris et al. (+2 more)
Robust single-vessel tracking from fixed coastal platforms is hindered by modality-specific degradations: cameras suffer from illumination and visual clutter, while
LiDAR performance drops with range and intermittent returns. We present a particle-filter tracker that supports sequential measurement-level camera-
LiDAR fusion and an information-gain (
entropy-reduction) adaptive sensing policy that selects the most informative sensing modality at each fusion time bin. The approach is validated in a real maritime deployment at the Cyprus Marine and Maritime Institute Smart Marina Testbed (Ayia Napa Marina, Cyprus), using a shore-mounted 3D
LiDAR and an elevated fixed camera to track a rigid inflatable boat with onboard GNSS ground truth. We compare
LiDAR-only, camera-only, All sensors, and adaptive configurations. Results show
LiDAR dominates near-field accuracy, the camera sustains longer-range coverage when
LiDAR becomes unavailable, and the adaptive policy achieves a favorable accuracy-continuity trade-off by switching modalities based on information gain. The adaptive configuration therefore provides a practical sensor-selection baseline for resilient and resource-aware maritime surveillance.
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All authors Andrei Starodubov, Yaqub Aris Prabowo, Andreas Hadjipieris, Ioannis Kyriakides, Roberto Galeazzi
Signal Processing
Graph Based Semantic Encoder Decoder Framework for Task Oriented Communications in Connected Autonomous Vehicles
Soheyb Ribouh and Phil Polo Ditsia Di Ngoma
Connected autonomous vehicles (CAVs) require reliable and efficient communication frameworks to support safety critical and task-oriented applications such as collision avoidance, cooperative perception, and traffic risk assessment. Traditional communication paradigms, which focus on transmitting raw bits, often incur excessive bandwidth consumption and fail to preserve the semantic relevance of transmitted information. To bridge this gap, we propose a Graph-Based Semantic Encoder-Decoder (GBSED) architecture tailored for task-oriented communications in CAV networks. The encoder leverages scene graphs to capture spatial and semantic relationships among road entities, combined with a semantic compression
algorithm that reduces the size of the extracted graph based representations by up to 99% compared to raw images, while the decoder reconstructs task relevant representations rather than raw data. This design enables a significant reduction in communication overhead while maintaining high semantic fidelity, exceeding 0.9 at SNR levels above 10dB, for downstream vehicular tasks. We evaluate the proposed framework through simulations in autonomous driving scenarios, where the semantic encoder and decoder are integrated into a
MIMO OFDM physical layer system. The results demonstrate high prediction success rates for risk assessment, improved robustness under the 3GPP CDL channel, and significant compression gains, confirming that the proposed semantic communication framework is a promising solution for future 6G systems.
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Systems and Control · Cross-listed from cs.AI
IronEngine: Towards General AI Assistant
Xi Mo
This paper presents IronEngine, a general AI assistant platform organized around a unified orchestration core that connects a desktop user interface, REST and WebSocket APIs, Python clients, local and cloud model backends, persistent
memory, task scheduling, reusable skills, 24-category tool execution, MCP-compatible extensibility, and hardware-facing integration. IronEngine introduces a three-phase pipeline – Discussion (Planner–Reviewer collaboration), Model Switch (VRAM-aware transition), and Execution (tool-augmented action loop) – that separates planning quality from execution capability. The system features a hierarchical
memory architecture with multi-level consolidation, a vectorized skill repository backed by ChromaDB, an adaptive model management layer supporting 92 model profiles with VRAM-aware context budgeting, and an intelligent tool routing system with 130+ alias normalization and automatic error correction. We present experimental results on file operation
benchmarks achieving 100% task completion with a mean total time of 1541 seconds across four heterogeneous tasks, and provide detailed comparisons with representative AI assistant systems including ChatGPT, Claude Desktop, Cursor, Windsurf, and open-source
agent frameworks. Without disclosing proprietary
prompts or core
algorithms, this paper analyzes the platform's architectural decomposition, subsystem design, experimental performance, safety boundaries, and comparative engineering advantages. The resulting study positions IronEngine as a system-oriented foundation for general-purpose personal assistants, automation frameworks, and future human-centered
agent platforms.
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Signal Processing
Subspace Fusion Sensing for Cooperative ISAC
Yining Xu, Cunhua Pan, Jun Tang et al. (+2 more)
This paper proposes a subspace fusion sensing
algorithm for cooperative integrated sensing and communication. First, we stack the received signals from access points (APs) into a third-order tensor and construct the equivalent virtual
antenna (EVA) array via tensor unfolding. Then, a data association-free subspace-based fusion sensing
algorithm is developed utilizing the EVA arrays from distributed APs. A derivation of Cramer-Rao lower bound (CRLB) is also presented. Finally, simulation results validate the effectiveness of the proposed
algorithm compared to traditional techniques.
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All authors Yining Xu, Cunhua Pan, Jun Tang, Hong Ren, Jiangzhou Wang
Signal Processing
Deep Learning based Cross-Receiver Radio Frequency Fingerprint Identification Under Varying Channels
Jiashuo He, Yumeng Wang, Feiyang He et al. (+4 more)
Radio frequency fingerprint identification (RFFI) exploits device-specific hardware impairments for transmitter recognition, but its performance is highly vulnerable to receiver variations and changing wireless channels in cross-receiver deployment. To address both challenges, this paper proposes a novel cross-receiver RFFI framework with channel robustness. In the enrollment stage, a channel-robust preprocessing method is developed to construct denoised spectral quotient (DSQ) sequences, and a DSQ-based convolutional neural network (DSQCNN) is trained using data collected from the source receiver. In the cross-receiver deployment stage, a calibration
dataset is built from signals captured by both the source and target receivers, and a trainable calibration neural network (TCNN) is designed to learn the nonlinear mapping between them. The cascaded TCNN-DSQCNN framework then enables robust transmitter classification on the target receiver under varying channel conditions. To the best of our knowledge, this is the first work to jointly address channel and receiver portability through combined channel suppression and nonlinear receiver calibration. Simulations with twelve WiFi transmitters and three receivers show that the proposed method achieves reliable cross-receiver classification, reaching over 90% accuracy at an SNR of 24 dB.
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All authors Jiashuo He, Yumeng Wang, Feiyang He, Sai Huang, Yiheng Liu, Shuo Chang, Zhiyong Feng
Audio and Speech Processing
NLE: Non-autoregressive LLM-based ASR by Transcript Editing
Avihu Dekel, Samuel Thomas, Takashi Fukada et al. (+1 more)
While autoregressive (AR) LLM-based ASR systems achieve strong accuracy, their sequential decoding limits parallelism and incurs high latency. We propose NLE, a non-autoregressive (NAR) approach that formulates
speech recognition as conditional transcript editing, enabling fully parallel prediction. NLE extracts acoustic
embeddings and an initial hypothesis from a pretrained
speech encoder, then refines the hypothesis using a bidirectional LLM editor trained with a latent
alignment objective. An interleaved padding strategy exploits the identity mapping bias of
Transformers, allowing the model to focus on corrections rather than full reconstruction. On the Open ASR leaderboard, NLE++ achieves 5.67% average WER with an RTFx (inverse real-time factor) of 1630. In single-utterance scenarios, NLE achieves 27x speedup over the AR baseline, making it suitable for real-time applications.
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All authors Avihu Dekel, Samuel Thomas, Takashi Fukada, George Saon
Signal Processing
Mitigating Mixed-field Interference in Near-field and Far-field Communications: An Antenna Selection Approach
Tianyu Liu, Changsheng You, Chao Zhou et al. (+3 more)
In mixed near-field and far-field systems, the nonorthogonality between near-field and far-field channels may cause severe inter-user interference and hence degrade rate performance, when the analog beamforming is designed based on the low-complexity full-array maximum ratio transmission (MRT). To tackle this issue, we propose in this paper an
antenna selection-based transmission framework to effectively suppress mixed-field interference without mechanically altering
antenna structures. To this end, an optimization problem is formulated to maximize the sum-rate of mixed-field systems, by jointly designing
antenna selection and power allocation under the MRT-based analog beamforming. As the problem is non-convex and generally difficult to solve optimally, we first consider a typical two-user scenario to obtain useful insights. Interestingly, we analytically show that the strong mixed-field interference can be substantially mitigated by deactivating only a small portion of
antennas, yet without compromising array gains too much. Moreover, an inherent tradeoff is revealed in
antenna selection between interference suppression and array-gain enhancement, based on which a suboptimal number of deactivated
antennas for achieving the maximum sum-rate is obtained. Next, for the general multi-user case, we develop an efficient penalty dual decomposition (PDD)-based two-layer framework to obtain its high quality solution by using the block coordinate descent (BCD) and successive convex approximation (SCA) techniques. To further reduce the computational complexity, a low-complexity
antenna deactivation strategy is proposed capitalizing on an interference suppression criterion. Last, numerical results demonstrate that the proposed scheme achieves a favorable trade-off between interference suppression and array gain loss, hence achieving significant performance gains over various baseline schemes.
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All authors Tianyu Liu, Changsheng You, Chao Zhou, Mingjiang Wu, Ming-Min Zhao, Zhaocheng Wang
Image and Video Processing
Rectified flow-based prediction of post-treatment brain MRI from pre-radiotherapy priors for patients with glioma
Selena Huisman, Nordin Belkacemi, Vera C. Keil et al. (+2 more)
Brain tumors result in 20 years of lost life on average. Standard therapies induce complex structural changes in the
brain that are monitored through MRI. Recent developments in artificial intelligence (AI) enable conditional
multimodal image generation from clinical data. In this study, we investigate AI-driven generation of follow-up MRI in patients with intracranial tumors through conditional image generation. This approach enables realistic modeling of post-radiotherapy changes, allowing for treatment optimization. The public SAILOR
dataset of 25 patients was used to create a 2D rectified flow model conditioned on axial slices of pre-treatment MRI and RT dose maps. Cross-
attention conditioning was used to incorporate temporal and chemotherapy data. The resulting images were validated with structural similarity index measure (SSIM), peak signal-to-noise ratio (PSNR), Dice scores and Jacobian determinants. The resulting model generates realistic follow-up MRI for any time point, while integrating treatment information. Comparing real versus predicted images, SSIM is 0.88, and PSNR is 22.82. Tissue
segmentations from real versus predicted MRI result in a mean Dice-Sørensen coefficient (DSC) of 0.91. The rectified flow (RF) model enables up to 250x faster inference than Denoising
Diffusion Probabilistic Models (DDPM). The proposed model generates realistic follow-up MRI in real-time, preserving both semantic and visual fidelity as confirmed by image quality metrics and tissue
segmentations. Conditional generation allows counterfactual simulations by varying treatment parameters, producing predicted morphological changes. This capability has potential to support adaptive treatment dose planning and personalized outcome prediction for patients with intracranial tumors. Code will be available upon peer-reviewed publication at: https://github.com/SelenaIHuisman/RF-GlioPREDICT
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All authors Selena Huisman, Nordin Belkacemi, Vera C. Keil, Joost Verhoeff, Szabolcs David
Audio and Speech Processing · Cross-listed from cs.CL
Computational modeling of early language learning from acoustic speech and audiovisual input without linguistic priors
Okko Räsänen
Learning to understand
speech appears almost effortless for typically developing infants, yet from an information-processing perspective, acquiring a
language from acoustic
speech is an enormous challenge. This chapter reviews recent developments in using computational models to understand early
language acquisition from
speech and audiovisual input. The focus is on self-supervised and visually grounded models of perceptual learning. We show how these models are becoming increasingly powerful in learning various aspects of
speech without strong linguistic priors, and how many features of early
language development can be explained through a shared set of learning principles-principles broadly compatible with multiple theories of
language acquisition and human cognition. We also discuss how modern learning simulations are gradually becoming more realistic, both in terms of input data and in linking model behavior to empirical findings on infant
language development.
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Systems and Control
Eigenvalue Patterns and Participation Analysis of Symmetric Renewable Energy Power Systems
Yao Qin, Yitong Li, Wei Wang et al. (+3 more)
State-space analysis is widely employed for examining power system dynamics but faces challenges in large-scale power systems integrated with numerous inverter-based resources (IBRs), where the significant increase of system states complicates modal analysis. Notably, renewable energy power systems often consist of multiple homogeneous generation units. This uniformity, termed
symmetry in this paper, can facilitate the system stability analysis.
Eigenvalue patterns and participation factors in three types of symmetric renewable energy power systems are investigated, including ideally-, quasi-, and group-symmetric systems. An ideally-symmetric (quasi-symmetric) system comprises a group of identical (similar) subsystems connected to an external grid. A system containing multiple such groups is termed group-symmetric. In these symmetric systems, two types of modes are defined to characterize different interactions: inner-group modes, which describe the interactions among subsystems within a single group, and group-grid modes, which describe the interactions between the groups and the external grid. A new concept termed group participation factor is also proposed to extend the use of conventional participation factors for repeated and close modes. In addition, the invariance properties of the inner-group modes and group-grid modes are discussed. The findings provide insights for stability analysis and targeted optimization in power systems. Theoretical advances are validated through numerical results and electromagnetic transient (EMT) simulations on example power systems of varied types and scales.
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All authors Yao Qin, Yitong Li, Wei Wang, Shaoze Zhou, Zheng Wei, Jinjun Liu
Signal Processing
Electrocardiogram Classification with Transformers Using Koopman and Wavelet Features
Sucheta Ghosh and Zahra Monfared
Electrocardiogram (ECG) analysis is vital for detecting cardiac abnormalities, yet robust automated classification is challenging due to the complexity and variability of physiological signals. In this work, we investigate
transformer-based ECG classification using features derived from the Koopman operator and wavelet transforms. Two tasks are studied: (1) binary classification (Normal vs. Non-normal), and (2) four-class classification (Normal, Atrial Fibrillation, Ventricular Arrhythmia, Block). We use Extended Dynamic Mode Decomposition (EDMD) to approximate the Koopman operator. Our results show that wavelet features excel in binary classification, while Koopman features, when paired with
transformers, achieve superior performance in the four-class setting. A simple hybrid of Koopman and wavelet features does not improve accuracy. However, selecting an appropriate EDMD dictionary – specifically a radial basis function dictionary with tuned parameters – yields significant gains, surpassing the wavelet-only baseline and the hybrid wavelet-Koopman system. We also present a Koopman-based reconstruction analysis for interpretable insights into the learned dynamics and compare against a recurrent neural network baseline. Overall, our findings demonstrate the effectiveness of Koopman-based feature learning with
transformers and highlight promising directions for integrating dynamical systems theory into time-series classification.
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Systems and Control
The coordination between TSO and DSO in the context of energy transition - A review
Hang Nguyen, Koen Kok, Trung Thai Tran et al. (+1 more)
Nowadays, energy transition is ongoing in many countries, aiming to reduce dependence on fossil fuels and CO2 emissions. Besides the positive impacts on the environment, this transition brings technical challenges to the system operators, such as the intricacies of energy system integration, diminishing uncertainty, and incentivizing customers with advanced transaction models. The coordination between the Transmission system operator (TSO) and the Distribution system operator (DSO) is one of the most important aspects of encountering these obstacles. This coordination enhances the utilization of flexibility from Distributed energy resources (DERs) by incentivizing the
market parties with better willingness to pay schemes. This paper provides an overview of the coordination schemes (CS), their classification, assessment of the current situation and the challenges associated with applying these schemes in practical context. The main purpose is to investigate the most effective way for TSO/DSOs to use the flexibility resource to maintain the balancing of the entire system while ensuring no congestion occurs in the network. A broad range of possible coordination schemes along with exploiting flexibility services is presented and the pros and cons are analyzed. Additionally, the study presents a general scenario that describes the interaction between the operators and the third party in providing service to the balancing
market, considering cases with and without coordination.
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All authors Hang Nguyen, Koen Kok, Trung Thai Tran, Phuong H. Nguyen
Systems and Control
Adaptive Tracking Control of Euler-Lagrange Systems with Time-Varying State and Input Constraints
Poulomee Ghosh and Shubhendu Bhasin
This paper presents an adaptive control framework for Euler-Lagrange (E-L) systems that enforces user-defined time-varying state and input constraints in the presence of parametric uncertainties and bounded disturbances. The proposed design integrates a time-varying barrier Lyapunov Function (TVBLF) with a saturated control law to guarantee constraint satisfaction without resorting to real-time optimization. A key contribution is the development of an offline, verifiable feasibility condition that certifies the existence of a feasible control policy for any prescribed pair of time-varying state and input envelopes. Additionally, we prove boundedness of all closed-loop signals. Real-time experiments conducted on a 2-DoF helicopter model validate the efficacy and practical viability of the proposed method.
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Systems and Control · Cross-listed from cs.LG
Learning efficient representations of complex constraints for scalable optimization
Yilin Wen, Yi Guo, Bo Zhao et al. (+4 more)
Complex constraints often make real-world optimization computationally prohibitive at the scale and speed required for operational decision-making. Here we introduce PolyFormer, a PIML framework that learns compact polytopic representations of the geometry induced by complex constraints. PolyFormer captures constraint-induced geometry and transforms it into efficient polytopic reformulations, reducing the complexity of downstream optimization and enabling the use of off-the-shelf solvers. Neural parameterizations further enable rapid adaptation to varying operating conditions without retraining. Through evaluations across three important problems, i.e., large-scale resource aggregation, network-constrained optimization, and optimization under uncertainty, PolyFormer achieves online solver speedups of up to 6,400-fold and
memory reductions of up to 99.87%, while maintaining small feasibility and objective errors. Together, these results establish learned
geometric constraint representations as an effective and scalable route to prescriptive optimization under diverse forms of constraint complexity.
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All authors Yilin Wen, Yi Guo, Bo Zhao, Wei Qi, Zechun Hu, Colin Jones, Jian Sun
Audio and Speech Processing
Bootstrapping Audiovisual Speech Recognition in Zero-AV-Resource Scenarios
Pol Buitrago and Javier Hernando
Audiovisual
speech recognition (AVSR) combines acoustic and visual cues to improve transcription robustness under challenging conditions but remains out of reach for most under-resourced
languages due to the lack of labeled
video corpora for training. Synthetic visual data have been shown to be an effective augmentation strategy for addressing AV data scarcity. However, a more challenging scenario arises for
languages such as Catalan, where no real audiovisual data are available for training. In this study, we investigate whether AVSR can be bootstrapped in such a zero-AV-resource setting, using synthetic visual data as the sole source of visual supervision. We synthesize over 700 hours of talking-head
video and fine-tune a pre-trained AV-HuBERT model. On a manually annotated Catalan
benchmark, our model achieves near state-of-the-art (SOTA) performance with much fewer parameters and training data than SOTA ASR systems such as Whisper-large-v3, outperforms an identically trained audio-only baseline, and preserves
multimodal advantages under acoustic degradation. Scalable synthetic
video thus offers a viable substitute for real recordings in zero-AV-resource AVSR.
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Systems and Control
Coupling Europe's Capacity Markets
Kamal Adekola, Laurens de Vries and Kenneth Bruninx
European Member States are increasingly introducing national capacity mechanisms (CMs) to manage growing adequacy risks. However, isolated national CMs are inefficient in highly interconnected electricity systems, such as the European system. While progress has been made in facilitating cross-border participation by generation capacity in CMs, existing arrangements are prone to under- or over-investment and do not properly value the contribution of interconnection capacity to Member States' adequacy targets. In this paper, we propose a novel conceptual design for a coupled European capacity
market that utilises the logic of flow-based
market coupling. In a comparative analysis of different
market design scenarios in an illustrative multi-zone case study, using a bespoke long-run
equilibrium problem, we show that the proposed flow-based coupling of capacity
markets reduces system costs by harnessing available capacity in neighbouring
market zones while ensuring deliverability with respect to network constraints in all scarcity situations.
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Signal Processing
Fluid Antennas Meet Intelligent Surfaces: Security Analysis of NOMA Systems Under Hardware Impairments
Tuo Wu, Jianchao Zheng, Xiazhi Lai et al. (+3 more)
The revolutionary convergence of fluid
antenna systems (FAS) and reconfigurable intelligent surfaces (RIS) creates unprecedented opportunities for secure wireless communications, yet the practical implications of hardware impairments on this promising combination remain largely unexplored. This paper investigates the security performance of non-orthogonal multiple access (NOMA) systems when fluid
antennas (FAs) meet intelligent surfaces under realistic hardware constraints. We develop a comprehensive analytical framework that captures the complex interplay between adaptive spatial diversity, intelligent signal reflection, and hardware-induced distortions in short-packet communications. Through novel piecewise linear approximations and block-correlation models, we derive tractable expressions for average secure block error rate (BLER) that reveal fundamental performance limits imposed by hardware impairments. Our analysis demonstrates that while the synergy between FAs and intelligent surfaces offers remarkable degrees of freedom for security enhancement, practical hardware imperfections create performance ceilings that persist regardless of spatial diversity gains. The theoretical framework exposes critical design trade-offs between system complexity and achievable security performance, showing that hardware quality becomes a decisive factor in realizing the full potential of FAS-RIS architectures. Extensive simulations validate our analytical insights and provide practical design guidelines for implementing secure NOMA systems that effectively balance the benefits of fluid-intelligent cooperation against the constraints of realistic hardware limitations.
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All authors Tuo Wu, Jianchao Zheng, Xiazhi Lai, Maged Elkashlan, Hyundong Shin, Naofal Al-Dhahir
Audio and Speech Processing
Quantifying Cross-Lingual Transfer in Paralinguistic Speech Tasks
Pol Buitrago, Oriol Pareras, Federico Costa et al. (+1 more)
Paralinguistic
speech tasks are often considered relatively
language-agnostic, as they rely on extralinguistic acoustic cues rather than lexical content. However, prior studies report performance degradation under cross-lingual conditions, indicating non-negligible
language dependence. Still, these studies typically focus on isolated
language pairs or task-specific settings, limiting comparability and preventing a systematic assessment of task-level
language dependence. We introduce the Cross-Lingual Transfer
Matrix (CLTM), a systematic method to quantify cross-lingual interactions between pairs of
languages within a given task. We apply the CLTM to two paralinguistic tasks, gender identification and speaker verification, using a
multilingual HuBERT-based encoder, to analyze how donor-
language data affects target-
language performance during fine-tuning. Our results reveal distinct transfer patterns across tasks and
languages, reflecting systematic,
language-dependent effects.
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All authors Pol Buitrago, Oriol Pareras, Federico Costa, Javier Hernando
Audio and Speech Processing · Cross-listed from cs.SD
Disentangling Reasoning in Large Audio-Language Models for Ambiguous Emotion Prediction
Xiaofeng Yu, Jiaheng Dong, Jean Honorio et al. (+3 more)
Speech emotion recognition plays an important role in various applications. However, most existing approaches predict a single
emotion label, oversimplifying the inherently ambiguous nature of human emotional expression. Recent large audio-
language models show promise in generating richer outputs, but their
reasoning ability for ambiguous emotional understanding remains limited. In this work, we reformulate ambiguous
emotion recognition as a distributional
reasoning problem and present the first systematic study of ambiguity-aware
reasoning in LALMs. Our framework comprises two complementary components: an ambiguity-aware objective that aligns predictions with human perceptual distributions, and a structured ambiguity-aware chain-of-thought supervision that guides
reasoning over emotional cues. Experiments on IEMOCAP and CREMA-D demonstrate consistent improvements across SFT, DPO, and GRPO training strategies.
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All authors Xiaofeng Yu, Jiaheng Dong, Jean Honorio, Abhirup Ghosh, Hong Jia, Ting Dang
Signal Processing
From Design to Validation: Preparing a LEO-Capable UE for End-to-End System Evaluation
Amedeo Giuliani, Pol Henarejos, Erislandy Mozo et al. (+5 more)
The extension of 5G connectivity through Low-Earth Orbit satellite systems introduces significant technical challenges, particularly due to time-varying propagation delays and high Doppler shifts resulting from satellite motion. While the Third Generation Partnership Project Release 17 established the initial framework for non-terrestrial networks, the ongoing developments in Release 19 further enhance this effort by introducing support for regenerative payload architectures, where part of the communication protocol stack is processed directly on board the satellite. In this work, we present the design of a 5G user equipment adapted for Low-Earth Orbit satellite connectivity, with specific focus on strategies for managing variable delay and Doppler compensation. Additionally, we describe a custom experimental platform based on a drone-mounted software-defined
radio platform capable of emulating both transparent and regenerative satellite payloads. Although full end-to-end system validation is not yet complete, initial laboratory tests confirm the feasibility of the architecture and lay the groundwork for future experimental campaigns.
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All authors Amedeo Giuliani, Pol Henarejos, Erislandy Mozo, Màrius Caus, Miguel Ángel Solis Gallego, Jaime Suárez García, Rami Othman, Justin Tallon
Image and Video Processing
3-D Near-Field Passive Radar Imaging Using Multiple Illumination Sources
Quanfeng Wang, Mei Song Tong and Thomas F. Eibert
Near-field (NF) passive radar imaging depends on the illumination of the imaging scene by a non-cooperative transmitter (Tx). It is demonstrated that combining imaging results obtained with Tx
antennas at different positions can enhance the performance of passive radar imaging. On the one hand, multiple Tx
antennas provide diverse illumination perspectives, reducing the likelihood of unilluminated regions on the targets of interest (TOIs). On the other hand, the coherent summation of imaging results obtained for different illuminations helps to suppress potential artifacts. This approach is in particular advantageous for imaging complex objects with concave structures such as dihedral arrangements, where the ghosts due to multiple reflections are highly configuration-dependent. For each illuminating configuration, a single-frequency inverse source solver is utilized to reconstruct the equivalent sources of the TOIs and the resulting single-frequency images are then superimposed coherently with corresponding phase and magnitude correction methods. The obtained multi-frequency images are finally coherently combined to enhance the imaging quality. Both simulation and measurement results are presented to validate the effectiveness of the approach.
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Audio and Speech Processing
DualTurn: Learning Turn-Taking from Dual-Channel Generative Speech Pretraining
Shangeth Rajaa
Speech-to-
speech models handle turn-taking naturally but offer limited support for tool-calling or complex
reasoning, while production ASR-LLM-TTS voice pipelines offer these capabilities but rely on silence timeouts, which lead to unnatural turn-taking. We present DualTurn, which narrows this gap through generative pretraining on dual-channel conversational audio. The model generates both speakers' future audio autoregressively, implicitly learning conversational dynamics without any labels, and is then fine-tuned to predict interpretable turn-taking signals that map directly to
agent actions. DualTurn monitors both channels continuously, anticipating turn boundaries and producing five
agent actions. On standard
benchmarks, DualTurn (0.5B) outperforms both VAP on
agent action prediction (wF1 0.633 vs. 0.389) and a 3.1B audio-text model on word-level turn prediction (AUC 0.930 vs. 0.880), while anticipating turn boundaries earlier with fewer interruptions.
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Image and Video Processing
Skill-Evolving Grounded Reasoning for Free-Text Promptable 3D Medical Image Segmentation
Tongrui Zhang, Chenhui Wang, Yongming Li et al. (+3 more)
Free-text promptable 3D medical image
segmentation offers an intuitive and clinically flexible interaction paradigm. However, current methods are highly sensitive to linguistic variability: minor changes in phrasing can cause substantial performance degradation despite identical clinical intent. Existing approaches attempt to improve robustness through stronger
vision-
language fusion or larger vocabularies, yet they lack mechanisms to consistently align ambiguous free-form expressions with anatomically grounded representations. We propose Skill-Evolving grounded
Reasoning (SEER), a novel framework for free-text promptable 3D medical image
segmentation that explicitly bridges linguistic variability and anatomical precision through a
reasoning-driven design. First, we curate the SEER-Trace
dataset, which pairs raw clinical requests with image-grounded, skill-tagged
reasoning traces, establishing a reproducible
benchmark. Second, SEER constructs an evidence-aligned target representation via a
vision-
language reasoning chain that verifies clinical intent against image-derived anatomical evidence, thereby enforcing semantic consistency before voxel-level decoding. Third, we introduce SEER-Loop, a dynamic skill-evolving strategy that distills high-reward
reasoning trajectories into reusable skill artifacts and progressively integrates them into subsequent inference, enabling structured self-refinement and improved robustness to diverse linguistic expressions. Extensive experiments demonstrate superior performance of SEER over state-of-the-art baselines. Under linguistic perturbations, SEER reduces performance variance by 81.94% and improves worst-case Dice by 18.60%. Project page: https://seer-medseg.github.io.
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All authors Tongrui Zhang, Chenhui Wang, Yongming Li, Zhihao Chen, Xufeng Zhan, Hongming Shan
Signal Processing
Instantaneous Frequency Estimation in Noisy Multicomponent Signals with Interfering Modes Based on Prony Method and Spline Approximation
Basile Dubois-Bonnaire, Sylvain Meignen and Kévin Polisano
In this paper, we propose a novel
estimator of the instantaneous frequencies (IFs) of the modes making up multicomponent signals (MCSs). We are particularly interested in dealing with noisy MCSs containing close modes in the time-frequency plane. Though it is possible to adapt Prony approach to estimate IFs in such situations, interference between the modes generates oscillations in the obtained estimations. After having investigated the nature of these oscillations, we propose an
algorithm to remove these in IFs estimation, based on spline approximation. Numerical applications in various situations illustrate the benefit of mixing Prony technique with spline approximation for IF estimation in noisy MCSs containing close modes.
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Signal Processing
Soft Fault Estimation and Localisation in Y-Shaped Networks using OFDM-Based Signals
Ameer Ahmadie
This paper introduces a method for detecting, estimating, and localising a soft fault in wired communication networks. The proposed method is based on analysing the transmission coefficients (TC) in the time domain under both fault-free and faulty situations. An orthogonal frequency-division multiplexing (OFDM)-based scheme is used to estimate the TC. A fault-severity ratio is derived to estimate the fault intensity, while a residual-based function is proposed to determine its location. Experimental validation is carried out on a Y-shaped test setup to demonstrate the efficiency of the proposed approach.
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Audio and Speech Processing
Privacy-Preserving End-to-End Full-Duplex Speech Dialogue Models
Nikita Kuzmin, Tao Zhong, Jiajun Deng et al. (+6 more)
End-to-end full-duplex
speech models feed user audio through an always-on LLM backbone, yet the speaker
privacy implications of their hidden representations remain unexamined. Following the VoicePrivacy 2024 protocol with a lazy-informed attacker, we show that the hidden states of SALM-Duplex and Moshi leak substantial speaker identity across all
transformer layers. Layer-wise and turn-wise analyses reveal that leakage persists across all layers, with SALM-Duplex showing stronger leakage in early layers while Moshi leaks uniformly, and that Linkability rises sharply within the first few turns. We propose two streaming anonymization setups using Stream-Voice-Anon: a waveform-level front-end (Anon-W2W) and a feature-domain replacement (Anon-W2F). Anon-W2F raises EER by over 3.5x relative to the discrete encoder baseline (11.2% to 41.0%), approaching the 50% random-chance ceiling, while Anon-W2W retains 78-93% of baseline sBERT across setups with sub-second response latency (FRL under 0.8 s).
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All authors Nikita Kuzmin, Tao Zhong, Jiajun Deng, Yingke Zhu, Tristan Tsoi, Tianxiang Cao, Simon Lui, Kong Aik Lee, Eng Siong Chng
Signal Processing · Cross-listed from math.OC
Outlier-robust Autocovariance Least Square Estimation via Iteratively Reweighted Least Square
Jiahong Li and Fang Deng
The autocovariance least squares (ALS) method is a computationally efficient approach for estimating noise covariances in Kalman filters without requiring specific noise models. However, conventional ALS and its variants rely on the classic least mean squares (LMS) criterion, making them highly sensitive to measurement outliers and prone to severe performance degradation. To overcome this limitation, this paper proposes a novel outlier-robust ALS
algorithm, termed ALS-IRLS, based on the iteratively reweighted least squares (IRLS) framework. Specifically, the proposed approach introduces a two-tier robustification strategy. First, an innovation-level adaptive thresholding mechanism is employed to filter out heavily contaminated data. Second, the outlier-contaminated autocovariance is formulated using an $\epsilon$-contamination model, where the standard LMS criterion is replaced by the Huber cost function. The IRLS method is then utilized to iteratively adjust data weights based on estimation deviations, effectively mitigating the influence of residual outliers. Comparative simulations demonstrate that ALS-IRLS reduces the root-mean-square error (RMSE) of noise covariance estimates by over two orders of magnitude compared to standard ALS. Furthermore, it significantly enhances downstream state estimation accuracy, outperforming existing outlier-robust Kalman filters and achieving performance nearly equivalent to the ideal Oracle lower bound in the presence of noisy and anomalous data.
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